Asian stocks slumped on the first trading day of September, with Japan's Nikkei 225 index chalking up a near 4 percent loss, after surveys of China's mammoth manufacturing sector showed a further loss of momentum in the world's second-biggest economy.

China's official manufacturingpurchasing managers' index (PMI) edged down to 49.7 in August from 50 in July, just below the 50-mark that separates expansion from contraction. Separately, the final Caixin/Markit manufacturingpurchasing managers' index (PMI) came in at 47.3 in August, above a preliminary reading of 47.1 but down from 47.8 in July.

"The data is hardly new. China's economic data have been weak for a long time," said Pruksa Iamthongthong, investment manager at Aberdeen Asset Management, who is underweight Chinese equities.

"We do see a fair bit of bloodbath in other sectors and across the market", she told CNBC's "Street Signs Asia" on Tuesday.

Among China's other indexes, the blue-chip CSI300 and smaller Shenzhen Composite receded 0.1 and 4.6 percent respectively, on Tuesday.

Hong Kong's Hang Seng index notched down nearly 1 percent on the first trading day of September.Last month, the Hang Seng index lost 12 percent, posting its fourth straight month of decline and the worst performance since September 2011.

Japan's benchmark Nikkei 225 index more than doubled losses in the afternoon trading session to finish nearly 4 percent lower, as weak manufacturing data out of China cast shadows on the health of the world's second-largest economy.

On the domestic front, corporate capital expenditure increased 5.6 percent in April-June from a year ago, slowing from the previous quarter and adding to signs of an economy struggling to recover from a slump.

"The index started comfortably above 5,200, but it was all downhill from there as investor sentiment took a number of hits, including a big retreat in Dow futures, the release of soft current account deficit data and further selling on Chinese exchanges as the manufacturing PMI [data] contained little to cheer about," analysts from Patersons Securities wrote in a note. Meanwhile, investors may be looking ahead to second-quarter gross domestic product (GDP) released on Wednesday is likely to sway market sentiment.

The country's biggest department store chain Myer said on Tuesday it would raise money from shareholders to cut debt and invest in its department stores after posting a 21 percent fall in full-year profit. The news weighed on fellow retailers such as Harvey Norman and JB Hi-Fi , which closed down 1.2 and 2 percent, respectively.

South Korea's Kospi index widened losses as a string of domestic data fueled worries about the country's economic growth prospects.

Manufacturing activity shrank for the sixth straight month in August, while exports posted their worst fall in six years as global demand wobbled. Following the data releases, Morgan Stanley downgraded its GDP forecasts for South Korea to 2.3 percent, from 2.5 percent for 2015, and calls for another interest rate cut.

"We believe that Korea's broken export growth model is a structural problem and will thus have a negative impact on Korea's growth for longer than previously expected," analysts Sharon Lam and Sung Woen Kang wrote in a note issued early Tuesday. "As growth is likely to disappoint, we now expect the Bank of Korea (BOK) to cut rates once again in fourth quarter to bring the policy rate to an unprecedented 1.25 percent. We believe this could take place as early as October."

According to Reuters, Australia and New Zealand Banking Group also cut its forecast for South Korea's 2015 economic growth by half a percentage point to 2.2 percent, which would be the slowest growth since 2009. ING, meanwhile, lowered its projection to 2.3 percent from the previous 2.5 percent.

Malaysia's FTSE Bursa Malaysia KLCI trimmed gains to 0.1 percent by late Tuesday, following a weekend demonstration in Kuala Lumpur that increased pressure on scandal-ridden Prime Minister Najib Razak. The ringgit held on to gains against the greenback, up nearly 1 percent at 4.1530, its highest level since August 21.

Vietnamese shares erased early gains to slip 0.5 percent even as new rules allowing foreigners to take bigger stakes in the country's equities took effect on Tuesday.

Meanwhile, India's BSE Sensex index and the 50-share Nifty index sagged more than 1 percent each, following data released late Monday which showed the country's economic growth slowing by more than expected in the second quarter.